An automatic sprinkler system is one of the most widely used devices for fire protection. These systems have sprinklers that are activated once the ambient temperature in an environment, such as a room or a building, exceeds a predetermined value. Once activated, the sprinklers distribute fire-extinguishing fluid, preferably water, in the room or building. A fire sprinkler system, depending on its specified configuration, is considered effective if it controls or suppresses a fire.
The sprinkler system can be provided with a water supply (e.g., a reservoir or a municipal water supply). Such supply may be separate from that used by a fire department. Regardless of the type of supply, the sprinkler system is provided with a main that enters the building to supply a riser. Connected at the riser are valves, meters, and, preferably, an alarm to sound when the system activates. Downstream of the riser, a usually horizontally disposed array of pipes extends throughout the fire compartment in the building. Other risers may feed distribution networks to systems in adjacent fire compartments. The sprinkler system can be provided in various configurations. In a wet-pipe system, used for example, in buildings having heated spaces for piping branch lines, all the system pipes contain a fire-fighting liquid, such as, water for immediate release through any sprinkler that is activated. In a dry-pipe system, used for example, in unheated areas, areas exposed to freezing, or areas where water leakage or unintended water discharge is normally undesirable or unacceptable such as, for example a residential occupancy, the pipes, risers, and feed mains, branch lines and other distribution pipes of the fire protection system may contain a dry gas (air or nitrogen or mixtures thereof) under pressure when the system is in a stand-by or unactuated condition. A valve is used to separate the pipes that contain the water. When heat from a fire activates a sprinkler, the gas escapes from the branch lines and the dry-pipe valve trips or actuates; water enters branch lines; and fire fighting begins as the sprinkler distributes the water.
One type of fluid control valve used to separate the gas filled pipes and liquid filled pipes is a diaphragm-type or diaphragm style valve, such as that shown in U.S. Patent Publication No. 2010/0071776, entitled “Fluid Control Valve Systems and Methods” or as shown in Tyco Fire Products published Data Sheet, TFP 1315 entitled, “Model DV-5 Deluge Valve, Diaphragm Style, 1-1.2 through 8 Inch (DN40 through DN 200) Deluge Systems—Dry Pilot Actuation.” (March 2004) (hereinafter “TFP1315”), each of which is incorporated by reference in their entireties. To control the flow of fluid between the inlet 5a and the outlet 5b and the respective wet and dry portions of the system 100, the preferred control valve 5 uses an internal diaphragm member having a sealed position and an open position to control the flow of fluid through the valve so as to respectively prevent and permit the flow of fluid from the wet portion of the system to the dry portion of the system. The position of the diaphragm is preferably controlled by fluid pressure acting on the internal diaphragm member.
One manner in which to control the fluid pressure in the diaphragm chamber of a fluid control valve is by way of a dry pilot actuator which is shown, for example in FIG. 4 (Parts 1-3) of TFP 1315 and in the particular known embodiment of a dry pilot actuator of Tyco Fire Products Data Sheet TFP 1380, entitled “Model DP-1: Dry Pilot Actuator For Deluge And Preaction Systems Dry Pilot Release Service” (May 2008) (hereinafter “TFP1380”) which is incorporated by reference in its entirety. The dry pilot actuator in TFP1380 also uses an internal diaphragm which acts against the fluid pressure in the diaphragm chamber of the fluid control valve to control actuation of the fluid control valve and displacement of the diaphragm member between its sealed and open positions. More specifically, gas pressure is used to regulate the position of the internal diaphragm of the pilot actuator to regulate the flow of fluid out of the diaphragm chamber of the fluid control valve so as to control the release of fluid from the wet portion of the system to the dry portion of the system. TFP1380 describes the minimum air pressure required to maintain the internal diaphragm of the dry pilot actuator in a sealed or closed position against a minimum water pressure of 20 psi. is about 25 psi.
There are patent publications which describe the control and monitor of dry type residential fire sprinkler protection systems. For example, U.S. Patent Publication No. 20080277125; U.S. patent application Ser. No. 11/916,419, entitled “Releasing Control Unit for Residential Fire Protection System,” which is incorporated herein by reference in its entirety. U.S. Patent Publication No. 20080277125 describes an electrically operated solenoid control valve. It may be desirable to have mechanically operated fluid control; and in particular, a dry-pilot actuated fluid control in a residential dry pipe fire protection system. Moreover, there may be a desire to have a dry-pilot actuator that can be maintained in a sealed condition at lower sealing gas pressures. Furthermore, it may be desired to have a dry-pilot actuator with a mechanical configuration that can serve as an alternate option to a diaphragm-type dry pilot actuator.